What characterizes a shrinkage crack in concrete?

A shrinkage crack in concrete is primarily characterized by its width, which is often no more than 1/8 inch. This type of crack occurs as a result of the natural drying and curing process of concrete, where moisture loss leads to the contraction of the material. As such, the width is generally modest, reflecting the fact that these cracks do not usually involve significant movement or displacement of the surrounding concrete.

In contrast, shrinkage cracks do not typically extend through the footings, nor are they associated with displacement on either side of the crack. They also tend to emerge relatively soon after the concrete is poured, rather than after several years, which distinguishes them from other types of cracks that may take longer to develop. These characteristics highlight that shrinkage cracks are usually superficial and primarily cosmetic issues rather than structural concerns.